<template>
  <div class="Rating-gray">
    <i v-for="(item,index) in itemClasses" :key="index" class="fa" :class="item" />
  </div>
</template>

<script>
// 星星长度
const LENGTH = 5
// 星星对应的class
const CLS_ON = 'fa-star'
const CLS_HALF = 'fa-star-half-empty'
const CLS_OFF = 'fa-star-o'

export default {
  name: 'Rating',
  props: {
    rating: Number
  },
  computed: {
    itemClasses() {
      // 4.8 四个全星 1个半星
      const result = []

      // 对分数进行处理, 向下取0.5的倍数
      const score = Math.floor(this.rating * 2) / 2
      // 控制半星
      const hasDecimal = score % 1 !== 0
      // 全星
      const integer = Math.floor(score)

      // 全星放入到数组中
      for (let i = 0; i < integer; i++) {
        result.push(CLS_ON)
      }

      // 半星
      if (hasDecimal) {
        result.push(CLS_HALF)
      }

      // 补齐
      while (result.length < LENGTH) {
        result.push(CLS_OFF)
      }

      return result
    }
  }
}
</script>

<style scoped>
.Rating-gray {
  margin-right: 1.066667vw;
  color: #ffbe00;
  display: inline-block;
}
</style>
